Nova-Like Cataclysmic Variables in the Infrared
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Naming the Extrasolar Planets
Naming the extrasolar planets W. Lyra Max Planck Institute for Astronomy, K¨onigstuhl 17, 69177, Heidelberg, Germany [email protected] Abstract and OGLE-TR-182 b, which does not help educators convey the message that these planets are quite similar to Jupiter. Extrasolar planets are not named and are referred to only In stark contrast, the sentence“planet Apollo is a gas giant by their assigned scientific designation. The reason given like Jupiter” is heavily - yet invisibly - coated with Coper- by the IAU to not name the planets is that it is consid- nicanism. ered impractical as planets are expected to be common. I One reason given by the IAU for not considering naming advance some reasons as to why this logic is flawed, and sug- the extrasolar planets is that it is a task deemed impractical. gest names for the 403 extrasolar planet candidates known One source is quoted as having said “if planets are found to as of Oct 2009. The names follow a scheme of association occur very frequently in the Universe, a system of individual with the constellation that the host star pertains to, and names for planets might well rapidly be found equally im- therefore are mostly drawn from Roman-Greek mythology. practicable as it is for stars, as planet discoveries progress.” Other mythologies may also be used given that a suitable 1. This leads to a second argument. It is indeed impractical association is established. to name all stars. But some stars are named nonetheless. In fact, all other classes of astronomical bodies are named. -
Biosignatures Search in Habitable Planets
galaxies Review Biosignatures Search in Habitable Planets Riccardo Claudi 1,* and Eleonora Alei 1,2 1 INAF-Astronomical Observatory of Padova, Vicolo Osservatorio, 5, 35122 Padova, Italy 2 Physics and Astronomy Department, Padova University, 35131 Padova, Italy * Correspondence: [email protected] Received: 2 August 2019; Accepted: 25 September 2019; Published: 29 September 2019 Abstract: The search for life has had a new enthusiastic restart in the last two decades thanks to the large number of new worlds discovered. The about 4100 exoplanets found so far, show a large diversity of planets, from hot giants to rocky planets orbiting small and cold stars. Most of them are very different from those of the Solar System and one of the striking case is that of the super-Earths, rocky planets with masses ranging between 1 and 10 M⊕ with dimensions up to twice those of Earth. In the right environment, these planets could be the cradle of alien life that could modify the chemical composition of their atmospheres. So, the search for life signatures requires as the first step the knowledge of planet atmospheres, the main objective of future exoplanetary space explorations. Indeed, the quest for the determination of the chemical composition of those planetary atmospheres rises also more general interest than that given by the mere directory of the atmospheric compounds. It opens out to the more general speculation on what such detection might tell us about the presence of life on those planets. As, for now, we have only one example of life in the universe, we are bound to study terrestrial organisms to assess possibilities of life on other planets and guide our search for possible extinct or extant life on other planetary bodies. -
Arxiv:2001.10147V1
Magnetic fields in isolated and interacting white dwarfs Lilia Ferrario1 and Dayal Wickramasinghe2 Mathematical Sciences Institute, The Australian National University, Canberra, ACT 2601, Australia Adela Kawka3 International Centre for Radio Astronomy Research, Curtin University, Perth, WA 6102, Australia Abstract The magnetic white dwarfs (MWDs) are found either isolated or in inter- acting binaries. The isolated MWDs divide into two groups: a high field group (105 − 109 G) comprising some 13 ± 4% of all white dwarfs (WDs), and a low field group (B < 105 G) whose incidence is currently under investigation. The situation may be similar in magnetic binaries because the bright accretion discs in low field systems hide the photosphere of their WDs thus preventing the study of their magnetic fields’ strength and structure. Considerable research has been devoted to the vexed question on the origin of magnetic fields. One hypothesis is that WD magnetic fields are of fossil origin, that is, their progenitors are the magnetic main-sequence Ap/Bp stars and magnetic flux is conserved during their evolution. The other hypothesis is that magnetic fields arise from binary interaction, through differential rotation, during common envelope evolution. If the two stars merge the end product is a single high-field MWD. If close binaries survive and the primary develops a strong field, they may later evolve into the arXiv:2001.10147v1 [astro-ph.SR] 28 Jan 2020 magnetic cataclysmic variables (MCVs). The recently discovered population of hot, carbon-rich WDs exhibiting an incidence of magnetism of up to about 70% and a variability from a few minutes to a couple of days may support the [email protected] [email protected] [email protected] Preprint submitted to Journal of LATEX Templates January 29, 2020 merging binary hypothesis. -
Arxiv:2006.10868V2 [Astro-Ph.SR] 9 Apr 2021 Spain and Institut D’Estudis Espacials De Catalunya (IEEC), C/Gran Capit`A2-4, E-08034 2 Serenelli, Weiss, Aerts Et Al
Noname manuscript No. (will be inserted by the editor) Weighing stars from birth to death: mass determination methods across the HRD Aldo Serenelli · Achim Weiss · Conny Aerts · George C. Angelou · David Baroch · Nate Bastian · Paul G. Beck · Maria Bergemann · Joachim M. Bestenlehner · Ian Czekala · Nancy Elias-Rosa · Ana Escorza · Vincent Van Eylen · Diane K. Feuillet · Davide Gandolfi · Mark Gieles · L´eoGirardi · Yveline Lebreton · Nicolas Lodieu · Marie Martig · Marcelo M. Miller Bertolami · Joey S.G. Mombarg · Juan Carlos Morales · Andr´esMoya · Benard Nsamba · KreˇsimirPavlovski · May G. Pedersen · Ignasi Ribas · Fabian R.N. Schneider · Victor Silva Aguirre · Keivan G. Stassun · Eline Tolstoy · Pier-Emmanuel Tremblay · Konstanze Zwintz Received: date / Accepted: date A. Serenelli Institute of Space Sciences (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E- 08193, Spain and Institut d'Estudis Espacials de Catalunya (IEEC), Carrer Gran Capita 2, Barcelona, E-08034, Spain E-mail: [email protected] A. Weiss Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany C. Aerts Institute of Astronomy, Department of Physics & Astronomy, KU Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium and Department of Astrophysics, IMAPP, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, the Netherlands G.C. Angelou Max Planck Institute for Astrophysics, Karl Schwarzschild Str. 1, Garching bei M¨unchen, D-85741, Germany D. Baroch J. C. Morales I. Ribas Institute of· Space Sciences· (ICE, CSIC), Carrer de Can Magrans S/N, Bellaterra, E-08193, arXiv:2006.10868v2 [astro-ph.SR] 9 Apr 2021 Spain and Institut d'Estudis Espacials de Catalunya (IEEC), C/Gran Capit`a2-4, E-08034 2 Serenelli, Weiss, Aerts et al. -
Abstracts of Extreme Solar Systems 4 (Reykjavik, Iceland)
Abstracts of Extreme Solar Systems 4 (Reykjavik, Iceland) American Astronomical Society August, 2019 100 — New Discoveries scope (JWST), as well as other large ground-based and space-based telescopes coming online in the next 100.01 — Review of TESS’s First Year Survey and two decades. Future Plans The status of the TESS mission as it completes its first year of survey operations in July 2019 will bere- George Ricker1 viewed. The opportunities enabled by TESS’s unique 1 Kavli Institute, MIT (Cambridge, Massachusetts, United States) lunar-resonant orbit for an extended mission lasting more than a decade will also be presented. Successfully launched in April 2018, NASA’s Tran- siting Exoplanet Survey Satellite (TESS) is well on its way to discovering thousands of exoplanets in orbit 100.02 — The Gemini Planet Imager Exoplanet Sur- around the brightest stars in the sky. During its ini- vey: Giant Planet and Brown Dwarf Demographics tial two-year survey mission, TESS will monitor more from 10-100 AU than 200,000 bright stars in the solar neighborhood at Eric Nielsen1; Robert De Rosa1; Bruce Macintosh1; a two minute cadence for drops in brightness caused Jason Wang2; Jean-Baptiste Ruffio1; Eugene Chiang3; by planetary transits. This first-ever spaceborne all- Mark Marley4; Didier Saumon5; Dmitry Savransky6; sky transit survey is identifying planets ranging in Daniel Fabrycky7; Quinn Konopacky8; Jennifer size from Earth-sized to gas giants, orbiting a wide Patience9; Vanessa Bailey10 variety of host stars, from cool M dwarfs to hot O/B 1 KIPAC, Stanford University (Stanford, California, United States) giants. 2 Jet Propulsion Laboratory, California Institute of Technology TESS stars are typically 30–100 times brighter than (Pasadena, California, United States) those surveyed by the Kepler satellite; thus, TESS 3 Astronomy, California Institute of Technology (Pasadena, Califor- planets are proving far easier to characterize with nia, United States) follow-up observations than those from prior mis- 4 Astronomy, U.C. -
The Giant Planet Orbiting the Cataclysmic Binary DP Leonis
Astronomy & Astrophysics manuscript no. dpleo c ESO 2018 October 7, 2018 The giant planet orbiting the cataclysmic binary DP Leonis K. Beuermann1, J. Buhlmann2, J. Diese2, S. Dreizler1, F. V. Hessman1, T.-O. Husser1, G. F. Miller4, N. Nickol2, R. Pons2, D. Ruhr2, H. Schm¨ulling2, A. D. Schwope3, T. Sorge2, L. Ulrichs2, D. E. Winget4, and K. I. Winget4 1 Institut f¨ur Astrophysik, Georg-August-Universit¨at, Friedrich-Hund-Platz 1, 37077 G¨ottingen, Germany, 2 Max-Planck-Gymnasium, Theaterplatz 10, 37073 G¨ottingen, Germany 3 Astrophysikalisches Institut Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany 4 Dept. of Astronomy, University of Texas at Austin, RLM 16.236, Austin, TX 78712, USA Received 18 October 2010 / accepted 12 November 2010 ABSTRACT Planets orbiting post-common envelope binaries provide fundamental information on planet formation and evolution, especially for the yet nearly unexplored class of circumbinary planets. We searched for such planets in DP Leo, an eclipsing short-period binary, which shows long-term eclipse-time variations. Using published, reanalysed, and new mid-eclipse times of the white dwarf in DPLeo, obtained between 1979 and 2010, we find agreement with the light-travel-time effect produced by a third body in an elliptical orbit. In particular, the measured binary period in 2009/2010 and the implied radial velocity coincide with the values predicted for the motion of the binary and the third body around the common center of mass. The orbital period, semi-major axis, and eccentricity of the third body are Pc = 28.0±2.0 yrs, ac = 8.2 ± 0.4 AU, and ec = 0.39±0.13. -
S. Dreizler 7 Öttingen, 2) Warwick, Öttingen,3) Austin, 4) Valparaiso,5) 2) Warwick, , , S
Planetary Systems of post-common envelope binaries Stefan Dreizler Institut für Astrophysik Göttingen PLATO Meeting Berlin Meeting PLATO Based on Two planets– orbiting the recently formed post-common envelope binary NN Serpentis A&A 521, L60 (2010) K. Beuermann1, F. V. Hessman1 , S. Dreizler1, T. R. Marsh2, S.G. Parsons2, D.E. Winget3, G. F. Miller3, M. R. Schreiber4, W. Kley5, V. S. Dhillon6, S. P. Littlefair6, C.M. Copperwheat2, J. J. Hermes3 The giant planet orbiting the cataclysmic binary DP Leonis A&A 526, 53 (2011) K. Beuermann1, J. Buhlmann2, J. Diese7, S. Dreizler1, F. V. Hessman1, T.-O. Husser1, G. F. Miller3, N. Nickol7, R. Pons7, D. Ruhr7, H. Schmülling7, A. D. Schwope8, T. Sorge7, L. Ulrichs7, D. E. Winget3 and K. I. Winget3 envelope binaries envelope Planetary systems of post common of systems Planetary 1) Göttingen, 2) Warwick, 3) Austin, 4) Valparaiso, 5) Tübingen, 6) Sheffield 7) Göttingen (MPG), 8) Potsdam AIP Post common enevelope binaries with companions • PCEB – result from spiraling in secondary in the RG envelope of the primary • Detection method – Eclipse-time variation by the light-travel time effect PLATO Meeting Berlin Meeting PLATO – – biased towards massive companions with long periods • Interpretation – Apparent period variation: third body, apsidal motion, beating between activity+orbital rotation – Real variation: magnetic braking, Applegate’s envelope binaries envelope Planetary systems of post common of systems Planetary mechanism, gravitational waves, ..... Post common enevelope binaries with companions • Systems – HW Vir 19 + 9 Mjup (Lee et al. 2009) – NN Ser 7+2 Mjup (Beuermann et al. 2010) – QS Vir 60 + 6 Mjup (Parsons et al. -
Our Universe
Journal of Aircraft and Spacecraft Technology Original Research Paper Our Universe 1Relly Victoria Petrescu, 2Raffaella Aversa, 3Bilal Akash, 4Juan Corchado, 2Antonio Apicella and 1Florian Ion Tiberiu Petrescu 1ARoTMM-IFToMM, Bucharest Polytechnic University, Bucharest, (CE ) Romania 2Advanced Material Lab, Department of Architecture and Industrial Design, Second University of Naples, 81031 Aversa (CE ) Italy 3Dean of School of Graduate Studies and Research, American University of Ras Al Khaimah, UAE 4Union College, USA Article history Abstract: It's hard to know ourselves and our role as humanity, without Received: 03-06-2017 knowing our precise location first. In the universe where we find ourselves Revised: 05-06-2017 (what we know not much about), there are billions of galaxies. A galaxy is Accepted: 15-06-2017 a large cluster of stars (suns), i.e., solar systems; on average an ordinary Corresponding Author: galaxy contains about two billion stars (suns), which may or may not have Florian Ion Tiberiu Petrescu planets around them. A constellation is a group of galaxies that depend on ARoTMM-IFToMM, Bucharest each other. Virgo is a very famous zodiacal constellation. Her name comes Polytechnic University, from Latin, the virgin and her symbol is ♍. The constellation of the Virgin Bucharest, (CE), Romania is located between the Lion to the west and the Libra to the east, being the E-mail: [email protected] second constellation in the sky (after Hydra) in size. The constellation of the Virgin can easily be observed in the sky of the earth due to its sparkling star named Spica. So our universe contains about two billion galaxies and many constellations; a constellation comprises several galaxies and a galaxy has about 2 billion stars. -
Planet Formation in Binaries 3
Noname manuscript No. (will be inserted by the editor) Planet formation in Binaries P. Thebault · N. Haghighipour the date of receipt and acceptance should be inserted later Abstract Spurred by the discovery of more than 60 exoplanets in multiple systems, binaries have become in recent years one of the main topics in planet formation re- search. Numerous studies have investigated to what extent the presence of a stellar companion can affect the planet formation process. Such studies have implications that can reach beyond the sole context of binaries, as they allow to test certain as- pects of the planet formation scenario by submitting them to extreme environments. We review here the current understanding on this complex problem. We show in par- ticular how each of the different stages of the planet-formation process is affected differently by binary perturbations. We focus especially on the intermediate stage of kilometre-sized planetesimal accretion, which has proven to be the most sensitive to binarity and for which the presence of some exoplanets observed in tight binaries is difficult to explain by in-situ formation following the ”standard” planet-formation scenario. Some tentative solutions to this apparent paradox are presented. The last part of our review presents a thorough description of the problem of planet habit- ability, for which the binary environment creates a complex situation because of the presence of two irradiation sources of varying distance. Keywords Planetary systems · Binary Stars 1 Introduction About half of solar-type stars reside in multiple stellar systems (Raghavan et al., 2010). As a consequence, one of the most generic environments to be considered for studying planet formation should in principle be that of a binary. -
Download This Issue (Pdf)
Volume 43 Number 1 JAAVSO 2015 The Journal of the American Association of Variable Star Observers The Curious Case of ASAS J174600-2321.3: an Eclipsing Symbiotic Nova in Outburst? Light curve of ASAS J174600-2321.3, based on EROS-2, ASAS-3, and APASS data. Also in this issue... • The Early-Spectral Type W UMa Contact Binary V444 And • The δ Scuti Pulsation Periods in KIC 5197256 • UXOR Hunting among Algol Variables • Early-Time Flux Measurements of SN 2014J Obtained with Small Robotic Telescopes: Extending the AAVSO Light Curve Complete table of contents inside... The American Association of Variable Star Observers 49 Bay State Road, Cambridge, MA 02138, USA The Journal of the American Association of Variable Star Observers Editor John R. Percy Edward F. Guinan Paula Szkody University of Toronto Villanova University University of Washington Toronto, Ontario, Canada Villanova, Pennsylvania Seattle, Washington Associate Editor John B. Hearnshaw Matthew R. Templeton Elizabeth O. Waagen University of Canterbury AAVSO Christchurch, New Zealand Production Editor Nikolaus Vogt Michael Saladyga Laszlo L. Kiss Universidad de Valparaiso Konkoly Observatory Valparaiso, Chile Budapest, Hungary Editorial Board Douglas L. Welch Geoffrey C. Clayton Katrien Kolenberg McMaster University Louisiana State University Universities of Antwerp Hamilton, Ontario, Canada Baton Rouge, Louisiana and of Leuven, Belgium and Harvard-Smithsonian Center David B. Williams Zhibin Dai for Astrophysics Whitestown, Indiana Yunnan Observatories Cambridge, Massachusetts Kunming City, Yunnan, China Thomas R. Williams Ulisse Munari Houston, Texas Kosmas Gazeas INAF/Astronomical Observatory University of Athens of Padua Lee Anne M. Willson Athens, Greece Asiago, Italy Iowa State University Ames, Iowa The Council of the American Association of Variable Star Observers 2014–2015 Director Arne A. -
Quantization of Planetary Systems and Its Dependency on Stellar Rotation Jean-Paul A
Quantization of Planetary Systems and its Dependency on Stellar Rotation Jean-Paul A. Zoghbi∗ ABSTRACT With the discovery of now more than 500 exoplanets, we present a statistical analysis of the planetary orbital periods and their relationship to the rotation periods of their parent stars. We test whether the structure of planetary orbits, i.e. planetary angular momentum and orbital periods are ‘quantized’ in integer or half-integer multiples with respect to the parent stars’ rotation period. The Solar System is first shown to exhibit quantized planetary orbits that correlate with the Sun’s rotation period. The analysis is then expanded over 443 exoplanets to statistically validate this quantization and its association with stellar rotation. The results imply that the exoplanetary orbital periods are highly correlated with the parent star’s rotation periods and follow a discrete half-integer relationship with orbital ranks n=0.5, 1.0, 1.5, 2.0, 2.5, etc. The probability of obtaining these results by pure chance is p<0.024. We discuss various mechanisms that could justify this planetary quantization, such as the hybrid gravitational instability models of planet formation, along with possible physical mechanisms such as inner discs magnetospheric truncation, tidal dissipation, and resonance trapping. In conclusion, we statistically demonstrate that a quantized orbital structure should emerge naturally from the formation processes of planetary systems and that this orbital quantization is highly dependent on the parent stars rotation periods. Key words: planetary systems: formation – star: rotation – solar system: formation 1. INTRODUCTION The discovery of now more than 500 exoplanets has provided the opportunity to study the various properties of planetary systems and has considerably advanced our understanding of planetary formation processes. -
Annual Report 2007 ESO
ESO European Organisation for Astronomical Research in the Southern Hemisphere Annual Report 2007 ESO European Organisation for Astronomical Research in the Southern Hemisphere Annual Report 2007 presented to the Council by the Director General Prof. Tim de Zeeuw ESO is the pre-eminent intergovernmental science and technology organisation in the field of ground-based astronomy. It is supported by 13 countries: Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Further coun- tries have expressed interest in member- ship. Created in 1962, ESO provides state-of- the-art research facilities to European as- tronomers. In pursuit of this task, ESO’s activities cover a wide spectrum including the design and construction of world- class ground-based observational facili- ties for the member-state scientists, large telescope projects, design of inno- vative scientific instruments, developing new and advanced technologies, further- La Silla. ing European cooperation and carrying out European educational programmes. One of the most exciting features of the In 2007, about 1900 proposals were VLT is the possibility to use it as a giant made for the use of ESO telescopes and ESO operates the La Silla Paranal Ob- optical interferometer (VLT Interferometer more than 700 peer-reviewed papers servatory at several sites in the Atacama or VLTI). This is done by combining the based on data from ESO telescopes were Desert region of Chile. The first site is light from several of the telescopes, al- published. La Silla, a 2 400 m high mountain 600 km lowing astronomers to observe up to north of Santiago de Chile.